chore: remove legacy benchmark

Author: pi0

package.json

@@ -33,15 +33,13 @@
     "lint:fix": "automd && eslint --fix . && prettier -w src test",
     "prepack": "unbuild",
     "release": "pnpm test && changelogen --release --push && pnpm publish",
-    "benchmark": "node benchmark/object-hash.mjs",
     "test": "pnpm lint && vitest run && pnpm test:types",
     "test:types": "tsc --noEmit"
   },
   "devDependencies": {
     "@types/node": "^22.13.4",
     "@vitest/coverage-v8": "^3.0.6",
     "automd": "^0.3.12",
-    "benchmark": "^2.1.4",
     "changelogen": "^0.5.7",
     "esbuild": "^0.25.0",
     "eslint": "^9.20.1",